How to maintain this garden dividing wall?

[parakeet]

The wall in the photos below is at the side-return passage of my Victorian mid-terraced house.
The paint has run since we moved in a year ago. There are a couple of holes and weeds. Many of the stones are smooth, look old/original.
I'm concerned about water being absorbed by the wall, and suspect water is tracking through the wall in to the adjacent room as damp.

What are the best ways to care for this wall, including any patching and repainting?
The aim being both to protect/seal and renew the aesthetics.
What techniques and what products?

Many thanks.

Untitled

• parakeet
• 7 Oct 2014
• 1

Untitled

• parakeet
• 7 Oct 2014
• 1

Untitled

• parakeet
• 7 Oct 2014
• 1

 

[gavingreyling]

best would be to break down and place new DPC and build back up again using plaster with a bit of bonding liquid.

the alternative is to take out only the stones and plaster and put it back with a new mix of plaster with bonding liquid.

the bonding liquid will help to stop the water penetration.